DMR - What is it?
W4BUG has made a big step for us. We decided to do our part to advance amateur radio by installing and operating a Motorola DMR repeater or use by the amateur community in our area. An DMR repeater is installed at the John Knox Village along with the 146.61 and the 442.500 repeaters that consists of the CAT800 controller. It uses the internet to connect to other DMR Talk Groups into other repeaters around the world with a little 5 Watt HT.
Surely, most operators are pretty much in the dark as to what DMR is and what it means to them. This page is an attempt to help explalin the system and start you on your way to understanding the system.
DMR (Digital Mobile Radio) is a digital voice and data protocol specification developed for use in Commerical radio but is now being used in amateur radio.
DMR compatible radios are available on VHF and UHF amateur radio bands but almost all of the DMR stuff is currently on UHF at this time. In addition to the over-the-air protocol, DMR also provides specifications for network connectivity by using various Talk Groups on one frequency, enabling DMR radios to be connected to the Internet or other networks. DMR is based on the Mortola MOTO Turbo type system.
As long as the signal strength is above a minimum threshold, the quality of the data received is better than an analog signal at the same strength. It is capable to linking other repeaters together and through the Internet by using Talk Groups, so HAMS may talk to another HAM radio in a different state or even a different country.
Another important aspect of DMR technology is its ability to send messages to emergency responders in the event of a disaster. Served agencies can instantly relate to sending messages to someone.
The gateway control software or C-Bridges are what link the talk groups together through the repeaters. Repeaters are not linked but the talk groups are linked via internet into local repeaters which allows for World Wide contacts via a 5 Watt HT.
Their are a few different networks out there and they are not all 100% compatable so check to see by looking them up on the internet.
The different networks are as follows:
BrandMeister ( Our Club Uses this one )
DMARC ( Motorola Based )
These are the most used.